San Diego Offshore Marine Forecast — Cortez Bank
Updated Mon Jul 20, 2026 · refreshed daily from the latest marine models
Caution all 3 days — cross-seas from S swell and NW wind-waves
Forecast for Jul 20–22, 2026
📋 Caution all 3 days — cross-seas from S swell and NW wind-waves
Caution all day Sunday due to a confused cross-sea with S swell crossing NW wind-waves, producing awkward motion on all headings. Seas reach 6.1 feet at 10-second periods from the SSW; winds are moderate at 8-12 knots NW. Best window is 10:00 AM–2:00 PM; avoid the overnight hours when winds and gusts are highest.
Monday stays at CAUTION as S swell crosses NW wind-waves for the first 16 hours, keeping seas confused near 5.7-5.8 feet at 10-second periods from the SW. Winds are the calmest of the forecast at 8-10 knots WNW mid-morning through afternoon. Overnight hours are windiest at 12-14 knots NW with gusts to 18 knots — avoid departing then.
Tuesday is the best day of the three, with the cross-sea between S swell and W wind-wave clearing after the first 6 hours and seas gradually easing to 5.0-5.5 feet at 10-11 second periods from the SSW. Winds are very light at 5-10 knots west all day. Best window is 2:00 PM–7:00 PM when winds and seas are at their lightest.
A persistent S swell running 5-6 feet at 10-second periods is crossing against a NW-to-W wind-wave throughout the entire forecast period, creating confused cross-seas that produce awkward, unpredictable motion regardless of heading. Winds themselves remain moderate and manageable at 8-14 knots across all three days, so the caution is driven entirely by the wave environment. Conditions improve gradually through Tuesday as the swell slowly eases, but the cross-sea pattern persists.
Recent days at Cortez Bank
About Cortez Bank
Cortez Bank is the serious end of San Diego offshore water — a remote, shallow seamount about 100 miles off San Diego, known for world-class fishing and the giant open-ocean swell that breaks at Bishop Rock. It is fully exposed: no island lee, no shelter, and swell that arrives with its full Pacific fetch intact. A careful read of swell height and period is essential before committing to the crossing.
The outlook below updates every morning from the latest marine model data, with a plain GO / CAUTION / NO-GO call for each day — the same AI rating used in the SeaLegs AI app.
Reading conditions at Cortez Bank
Long-period Pacific swell is the defining variable out here. The same 5-foot reading can be a well-organized 13-second swell that a sportfisher rides comfortably — or a shorter, wind-driven sea that makes the whole crossing a grind. Read the period next to the height on every day card above, and watch for the afternoon westerly reinforcement that often stiffens the ride home.
Because the bank is shallow water standing in deep ocean, swell energy focuses over it — conditions on the bank itself can be rougher than the open-water forecast either side of it. Build margin into the plan: the best Cortez days in the outlook are the ones where wind stays light through the full window, not just the morning.
Cortez Bank forecast FAQ
How far is Cortez Bank from San Diego?
Cortez Bank lies about 100 miles off San Diego — a genuine open-ocean crossing with no shelter along the way, which is why the multi-day outlook matters more here than for nearshore trips.
How often is this San Diego offshore forecast updated?
The forecast on this page is rebuilt every morning from the latest marine model data, and the SpotCast card refreshes live in your browser. The date stamp above the outlook shows when it was last generated.
What do GO, CAUTION, and NO-GO mean?
GO means conditions are favorable for most recreational offshore boats. CAUTION means marginal — pay close attention to swell period and the evening wind trend before committing to the crossing. NO-GO means conditions are hazardous for small craft and the trip is best postponed.
Can I get a forecast like this for my own spot?
Yes. In the free SeaLegs AI app you can drop a pin anywhere — the 9-Mile Bank, the Coronados, or your own waypoint — and get the same AI-rated marine forecast, plus fishing reports and trip planning.
More offshore forecasts
Get this forecast for your own spot
Drop a pin on any spot on planet Earth in the free SeaLegs AI app — AI marine forecasts, fishing reports, and trip planning, rated GO / CAUTION / NO-GO.
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